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Author Topic: nice two valve heads  (Read 1888 times)

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Offline turboguzzi

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nice two valve heads
« on: February 19, 2012, 09:18:48 AM »
not for honda, its stuff for italian battle of the twins ducs, but just interesting what people are doing to good old two valve heads.

very flat CC, plenty of squish area but most interesting is the port divider

www.gg2.it
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Offline Bill/BentON Racing

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Re: nice two valve heads
« Reply #1 on: February 19, 2012, 12:07:03 PM »
TG,only on intake,must weld,machine for guide and valve? What are their claims? Haven't seen this before.Bill
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Offline trueblue

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Re: nice two valve heads
« Reply #2 on: February 20, 2012, 02:03:28 AM »
You may notice that head is for a twin spark engine, that fin in the port would be there to direct the air flow towards the spark plugs, thats my best guess anyways.
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Offline turboguzzi

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Re: nice two valve heads
« Reply #3 on: February 20, 2012, 02:28:49 AM »
spoke with the guy at the stand they had in this weekend's major swapmeet in milan

he claimed that the fin reduces flow losses around the valve guide/ valve stem.

makes sense to me...

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Offline trueblue

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Re: nice two valve heads
« Reply #4 on: February 20, 2012, 02:35:06 AM »
Quote from: turboguzzi on February 20, 2012, 02:28:49 AM
spoke with the guy at the stand they had in this weekend's major swapmeet in milan

he claimed that the fin reduces flow losses around the valve guide/ valve stem.

makes sense to me...


I would believe that too, I would like to see some flow bench results to see how much difference it actually makes. 
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1979 CB650Z
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Offline mec

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Re: nice two valve heads
« Reply #5 on: February 20, 2012, 03:21:45 AM »
nice feature,

two thoughts:
would like to see it in the ex-port too
is it worth all the effort??

mec
« Last Edit: February 20, 2012, 04:24:18 AM by mec »
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Offline turboguzzi

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Re: nice two valve heads
« Reply #6 on: February 20, 2012, 03:52:45 AM »
well, 105hp from a two valve air-cooled 900 twin sounds pretty nice to me :)

they got dyno graphs in the site



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Offline trueblue

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Re: nice two valve heads
« Reply #7 on: February 21, 2012, 02:09:50 AM »
In the exhaust port there would be the possibility of the little fin collecting carbon, also the exhaust port isn't as critical as the intake as far a flow goes. 
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Offline MRieck

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Re: nice two valve heads
« Reply #8 on: February 21, 2012, 08:17:10 AM »
I have seen that before on car stuff and Harleys. I have seen a fin on the intake port floor at the entrance of the port on Harleys as well. I think it is more effective on large ports, large seat ID's with large valves.
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